I could cheat & just consult my copy of The Saleen Book quoting verbatim from Saleen's official compendium of their 1989 upgrades, but instead I'll simply try to do it from memory based on my own original owner '89 Saleen:
Racecraft
suspension: specific rate coil springs, urethane stablizer bar bushings, upper strut tower brace, lower K-member brace, SVO onion head upper strut mounts, Monroe Formula GP struts, shocks & horizontal rear axle dampers, specially calibrated alignment settings.
Saleen air management system: front & rear spoilers, side skirts, rear diffuser.
SVO five lug, four wheel disc brake system.
American Racing Enterprises 5-spoke aluminum wheels, 16x7 front, 16x8 rear ('87-'88 style ARE basket weave wheels optional).
General Tire XP2000V 225/50-16 tires.
Interior: Flofit front sport seats with adjustable lumbar & thigh supports, matching rear seat upholstery, Saleen Mustang embroidered door panels,
MOMO Monte Carlo steering wheel with cruise control bracket, Saleen leather shift knob & boot, Saleen/
Hurst quick ratio shifter, Saleen electronic 170 mph speedometer & tachometer, Saleen serialization plaque on console, Saleen emblem on passenger dashpad, Pioneer remote control stereo system (cassette player, graphic EQ/amplifier, wired remote control on console, front door/dash & rear side panel speakers).
Exterior graphics: Saleen windshield banner, Saleen Mustang on rear deck lid, 302 on hood, Racecraft
Suspension on front fenders, lower 'S' side stripes, upper belt line pin stripe.
Engine compartment serialization plate on firewall, Saleen OEM certification decal on driver's side door jamb.
Optional equipment: Heavy duty 3.55 ratio rear differential.